arXiv subjects

J. C. Phillips

Publications and source records attributed to J. C. Phillips.

At least 91 records · Page 5Linked to original sources

arXiv2006

Microscopic Filamentary Theory of Electronic Intermediate Phases

The self-organized dopant percolative filamentary model, entirely orbital in character (no spins), is strongly influenced by background (in)homogeneities. In the high temperature superconductive (HTSC) cuprates, pseudogap regions produce novel percolative features in phase diagrams. The model is especially successful in describing the appearance of giant magnetic vortex "precursive" effects at temperatures ~2 Tc far above the superconductive transition temperature Tc.

cond-mat.supr-con↗

arXiv2006

Self-Organized Networks and Lattice Effects in High Temperature Superconductors

The entirely orbital self-organized dopant percolative filamentary model describes many counter-intuitive chemical trends in oxide superconductors quantitatively, especially the high superconductive transition temperatures Tc. According to rules previously used successfully for network glasees, the host networks are marginally stable mechanically, and the high Tc's are caused by network softening, which produces large electron-phonon interactions at interlayer dopants for states near the Fermi energy.

cond-mat.supr-con↗

arXiv2005

Microscopic Spectral Model of High Temperature Superconductors

The self-organized dopant percolative filamentary model, entirely orbital in character (no spins), explains the evolution with doping of Fermi arcs observed by ARPES, including the abrupt transitions in quasiparticle strength observed near optimal doping in cuprate high temperature superconductors. Similarly abrupt transitions are also observed in time-resolved picosecond relaxation spectroscopy at 1.5 eV, and these are explained as well, using no new assumptions and no adjustable parameters. The anomalous "precursive" temperature-dependent strains observed by EXAFS are associated with relaxation of filamentary ends.

cond-mat.supr-con↗

arXiv2005

Ideally Glassy Hydrogen Bonded Networks

The axiomatic theory of ideally glassy networks, which has proved effective in describing phase diagrams and properties of chalcogenide and oxide glasses and their foreign interfaces, is broadened here to include intermolecular interactions in hydrogen-bonded polyalcohols such as glycerol, monosaccharides (glucose), and the optimal bioprotective hydrogen-bonded disaccharide networks formed from trehalose. The methods of Lagrangian mechanics and Maxwellian scaffolds are useful at the molecular level when bonding hierarchies are characterized by constraint counting similar to the chemical methods used by Huckel and Pauling. Whereas Newtonian molecular dynamical methods are useful for simulating large-scale interactions for times of order 10 ps, constraint counting describes network properties on glassy (almost equilibrated) time scales, which may be of cosmological order for oxide glasses, or years for trehalose. The ideally glassy network of trehalose may consist of extensible tandem sandwich arrays.

cond-mat.soft↗

arXiv2005

Ideal Glasses and Protein Network Dynamics

Quantitative topological analogies between the flexibilities of optimized inorganic glasses, small biological molecules, and proteins suggest that mean field estimates of internal stress are useful in identifying mechanisms supporting living materials and their enzymatic products. These analogies bode well for emerging minimalist flexibility models of protein dynamics. Application to trehalose, the optimal bioprotective material, leads to a remarkably simple mechanical model, closely parallel to mechanical effects observed in sandwich-like proteins.

cond-mat.soft↗

arXiv2005

Axiomatic Theories of Intermediate Phases (IP) and Ideal Stretched Exponential Relaxation (SER)

Minimalist theories of complex systems are broadly of two kinds: mean-field and axiomatic. So far all theories of properties absent from simple systems and intrinsic to complex systems, such as IP and SER, are axiomatic. SER is the prototypical complex temporal property of glasses, discovered by Kohlrausch 150 years ago, and now observed almost universally in microscopically homogeneous, complex non-equilibrium materials (strong network and fragile molecular glasses, polymers and copolymers, even electronic glasses). The Scher-Lax trap model (1973) is paradigmatic for electronic SER; for molecular SER Phillips (3RCS 1995) identified two "magic" shape fractions β= 3/5 and 3/7, as confirmed by many later experiments here reviewed. In the dielectric SER frequency domain involving ion conduction, there are also special beta values for fused salts and glasses, slightly, but distinguishably, different because of the presence of a forcing electric field.

cond-mat.soft↗

arXiv2005

Slow Dynamics in Glasses

Minimalist theories of complex systems are broadly of two kinds: mean-field and axiomatic. So far all theories of complex properties absent from simple systems and intrinsic to glasses are axiomatic. Stretched Exponential Relaxation (SER) is the prototypical complex temporal property of glasses, discovered by Kohlrausch 150 years ago, and now observed almost universally in microscopically homogeneous, complex non-equilibrium materials, including luminescent electronic (Coulomb) glasses. Critical comparison of alternative axiomatic theories with both numerical simulations and experiments strongly favors dynamical trap models over static percolative or energy landscape models. PACS: 61.20.Lc; 67.40.Fd

cond-mat.soft↗

arXiv2005

Self-Organization and the Physics of Glassy Networks

Network glasses are the physical prototype for many self-organized systems, ranging from proteins to computer science. Conventional theories of gases, liquids, and crystals do not account for the strongly material-selective character of the glass-forming tendency, the phase diagrams of glasses, or their optimizable properties. A new topological theory, only 25 years old, has succeeded where conventional theories have failed. It shows that (probably all slowly quenched) glasses, including network glasses, are the result of the combined effects of a few simple mechanisms. These glass-forming mechanisms are topological in nature, and have already been identified for several important glasses, including chalcogenide alloys, silicates (window glass, computer chips), and proteins.

cond-mat.dis-nn↗

arXiv2004

Topological derivation of shape exponents for stretched exponential relaxation

In homogeneous glasses, values of the important dimensionless stretched-exponential shape parameter beta are shown to be determined by magic (not adjusted) simple fractions derived from fractal configuration spaces of effective dimension d* by applying different topological axioms (rules) in the presence (absence) of a forcing electric field. The rules are based on a new central principle for defining glassy states: equal a priori distributions of fractal residual configurational entropy. Our approach and its beta estimates are fully supported by the results of relaxation measurements involving many different glassy materials and probe methods. The present unique topological predictions for beta typically agree with observed values to ~ 1% and indicate that for field-forced conditions beta should be constant for appreciable ranges of such exogenous variables as temperature and ionic concentration, as indeed observed using appropriate data analysis. The present approach can also be inverted and used to test sample homogeneity and quality.

cond-mat.mtrl-sci↗

arXiv2004

Topological Theory of Electron-Phonon Interactions in High Temperature Superconductors

There are large isotope effects in the phonon kinks observed in photoemission spectra (ARPES) of optimally doped cuprate high temperature superconductors (HTSC), but they are quite different (Gweon et al. 2004) from those expected for a nearly free electron metal with strong electron-phonon interactions (Tang et al. 2003). These differences, together with many other anomalies in infrared spectra, seem to suggest that other particles (such as magnons) must be contributing to HTSC. Here we use topological (non-Hamiltonian) methods to discuss the data, emphasizing nanoscale phase separation and the importance of a narrow band of quantum percolative states near the Fermi energy that is spatially pinned to a self-organized filamentary dopant array. Topological discrete, noncontinuum, nonperturbative methods have previously explained the form of HTSC phase diagrams without involving detailed microscopic assumptions, and they are especially useful in the presence of strong nanoscale disorder. These methods also explain the ``miracle'' of an ideal nearly free electron phonon kink in sharply defined nodal quasiparticle states in LSCO at the metal-insulator transition. Finally the universality of the kink energy and Fermi velocity in different cuprates is the result of the marginally elastic nature of these materials, and specifically the isostatic character of the CuO2 planes.

cond-mat.supr-con↗

arXiv2004

Superconductive Excitations and the Infrared Vibronic Spectra of BSCCO

The oxygen dopant concentration dependence of the "quasiparticle" feature at 600-750 cm-1 of the infrared spectrum of Bi2Sr2CaCu2O8+delta (BSCCO), lying near and above the top of the host phonon spectrum at 600 cm-1, is strongly correlated with superconductivity. Using parameter-free topological methods, theory assigns this feature to split apical oxygen interstitials. It explains both the qualitative similarities and the quantitative differences between "quasiparticle" features identified in infrared and phtoemission data, as well as identifying new features in the infrared spectra.

cond-mat.supr-con↗

arXiv2004

Why Are Cuprates the Only High-Temperature Superconductors?

The heirarchical mean-field theory of elastic networks, originally developed by Maxwell to discuss the stability of scaffolds, and recently applied to atomic networks by Phillips and Thorpe, explains the phase diagrams and remarkable superconductive properties of cuprates as the result of giant electron-phonon interactions in a marginally unstable mechanical network. The overall cuprate networks are fragile (floppy), as shown quantitatively (with an accuracy ~1 percent), and without adjustable parameters, by comparison with stabilities of generically similar network glasses, and are stabilized by percolative backbones composed of CuO2 planes.

cond-mat.supr-con↗

arXiv2004

Nonperturbative Topological Model of Synergistic Phase of 2D Electron Gas Induced by Microwave Excitation

The synergistic formation of ``zero'' (exponentially small or thermally activated) resistance states (ESRS) in high mobility two-dimensional electron systems (2DES) in a static magnetic field B and exposed to strong microwave radiation has attracted great interest. Strong (glassy) disorder apparently stabilizes the new synergistic phase, which can be exactly described by a nonperturbative (nonpolynomial) microscopic topological filamentary model. The model contains many novel features that arise from strong correlations, nanoscopic phase separation, and quasi-one dimensional back scattering.

cond-mat.mes-hall↗

arXiv2003

Fermats last theorem, the Riemann hypothesis, and synergistic glasses

The synergistic formation of zero (exponentially small) resistance states (ESRS) in high mobility two-dimensional electron systems (2DES) in a static magnetic field B and exposed to strong microwave (MW) radiation exhibits hysteresis and an anomalous logarithmic dependence on MW power. These synergistically organized states appear to be associated with a new kind of energy gap Δ. Here I show that a microscopic quantum model that involves the Prime Number Theorem explains the MW power dependence of the energy gap Δ. The explanation involves remarkable convergence with the most abstract ideas of modern mathematics.

cond-mat.mes-hall↗

arXiv2003

Network Topology and Subgap Resonances Observed by Fourier Transform Scanning Tunnelling Microscopy in Cuprate High-Temperature Superconductors

Fourier transform scanning tunneling microscopy on BSCCO subgap resonances has deciphered an octet of "quasi-particle" states that are consistent with the Fermi surface and energy gap observed by ARPES, but the origin of the high-intensity k-space octets and the sharply defined r-space checkerboard is unexplained. The filamentary ferroelastic nanodomain model that predicted the r-space checkerboard also explains the k-space octets and the origin of the apparent anisotropic surface d-wave gap by using strong electron-phonon interactions outside the CuO2 planes. The topological model identifies the factors that stabilize high-intensity k-space octets in the presence of a very high level of irregular r-space checkerboard noise.

cond-mat.supr-con↗

arXiv2003

Nanoscopic Filters as the Origin of d Wave Energy Gaps

A ferroelastic nanoscopic checkerboard pattern of pseudo- and superconductive gaps has been resolved by scanning tunneling microscopy on BSCCO. Using this pattern one can derive [not assume] a macroscopic anisotropic d wave superconductive energy gap that agrees well with angle-resolved photoemission and Fourier transform scanning tunneling microscopy data. The derivation is orbital only [no spins], it explains chemical trends in Raman scattering peak positions and strengths, and it predicts an unexpected reversal of anisotropic Raman gap signatures between BSCCO and LSCO, in good agreement with experiment.

cond-mat.supr-con↗

arXiv2003

Microscopic origin of collective exponentially small resistance states

The formation of "zero" (exponentially small) resistance states (ESRS) in high mobility two-dimensional electron systems (2DES) in a static magnetic field B and subjected to strong microwave (MW) radiation has attracted great theoretical interest. These states appear to be associated with a new kind of energy gap $Δ$. Here I show that the energy gap $Δ$ is explained by a microscopic quantum model that involves the Prime Number Theorem, hitherto reserved for only mathematical contexts.

cond-mat.mtrl-sci↗

arXiv2003

New collective zero-resistance states in GaAs/AlGaAs heterostructures

Exponentially small resistance in crossed static magnetic and microwave fields occurs in ultrapure two dimensional electron gases (2DEG), while in less pure systems the magnetoresistance oscillates but is always positive. A non-perturbative theory of self-organization explains the new collective states in terms of open orbits. There are analogies to many other anomalous physical phenomena, as well as to scaling and evolutionary principles of biophysics.

cond-mat.mes-hall↗